BRIDGE(8) Linux BRIDGE(8)
NAME
bridge - show / manipulate bridge addresses and devices
SYNOPSIS
bridge [ OPTIONS ] OBJECT { COMMAND | help }
OBJECT := { link | fdb | mdb | vlan | vni | monitor }
OPTIONS := { -V[ersion] | -s[tatistics] | -n[etns] name | -b[atch] file-
name | -com[pressvlans] | -c[olor] | -p[retty] | -j[son] |
-o[neline] }
bridge link set dev DEV [ cost COST ] [ priority PRIO ] [ state STATE ]
[ guard { on | off } ] [ hairpin { on | off } ] [ fastleave { on
| off } ] [ root_block { on | off } ] [ learning { on | off } ]
[ learning_sync { on | off } ] [ flood { on | off } ] [ hwmode {
vepa | veb } ] [ bcast_flood { on | off } ] [ mcast_flood { on |
off } ] [ mcast_max_groups MAX_GROUPS ] [ mcast_router MULTI-
CAST_ROUTER ] [ mcast_to_unicast { on | off } ] [ neigh_suppress
{ on | off } ] [ neigh_vlan_suppress { on | off } ] [ vlan_tun-
nel { on | off } ] [ isolated { on | off } ] [ locked { on | off
} ] [ mab { on | off } ] [ backup_port DEVICE ] [ nobackup_port
] [ backup_nhid NHID ] [ self ] [ master ]
bridge link [ show ] [ dev DEV ] [ master DEVICE ]
bridge fdb { add | append | del | replace } LLADDR dev DEV { local |
static | dynamic } [ self ] [ master ] [ router ] [ use ] [ ex-
tern_learn ] [ sticky ] [ src_vni VNI ] { [ dst IPADDR ] [ vni
VNI ] [ port PORT ] [ via DEVICE ] | nhid NHID }
bridge fdb [ [ show ] [ br BRDEV ] [ brport DEV ] [ vlan VID ] [ state
STATE ] [ dynamic ] ]
bridge fdb get [ to ] LLADDR [ br BRDEV ] { brport | dev } DEV [ vlan
VID ] [ vni VNI ] [ self ] [ master ] [ dynamic ]
bridge fdb flush dev DEV [ brport DEV ] [ vlan VID ] [ src_vni VNI ] [
nhid NHID ] [ vni VNI ] [ port PORT ] [ dst IPADDR ] [ self ] [
master ] [ [no]permanent | [no]static | [no]dynamic ] [
[no]added_by_user ] [ [no]extern_learn ] [ [no]sticky ] [
[no]offloaded ] [ [no]router ]
bridge mdb { add | del | replace } dev DEV port PORT grp GROUP [ src
SOURCE ] [ permanent | temp ] [ vid VID ] [ filter_mode { in-
clude | exclude } ] [ source_list SOURCE_LIST ] [ proto PROTO ]
[ dst IPADDR ] [ dst_port DST_PORT ] [ vni VNI ] [ src_vni
SRC_VNI ] [ via DEV ]
bridge mdb show [ dev DEV ]
bridge mdb get dev DEV grp GROUP [ src SOURCE ] [ vid VID ] [ src_vni
SRC_VNI ]
bridge mdb flush dev DEV [ port PORT ] [ vid VID ] [ src_vni SRC_VNI ] [
proto PROTO ] [ [no]permanent ] [ dst IPADDR ] [ dst_port
DST_PORT ] [ vni VNI ]
bridge mst set dev DEV msti MSTI state STP_STATE
bridge mst [ [ show ] [ dev DEV ] ]
bridge vlan { add | del } dev DEV vid VID [ tunnel_info TUNNEL_ID ] [
pvid ] [ untagged ] [ self ] [ master ]
bridge vlan set dev DEV vid VID [ state STP_STATE ] [ mcast_max_groups
MAX_GROUPS ] [ mcast_router MULTICAST_ROUTER ] [ neigh_suppress
{ on | off } ]
bridge vlan [ show | tunnelshow ] [ dev DEV ]
bridge vlan global set dev DEV vid VID [ mcast_snooping MULTICAST_SNOOP-
ING ] [ mcast_querier MULTICAST_QUERIER ] [ mcast_igmp_version
IGMP_VERSION ] [ mcast_mld_version MLD_VERSION ] [
mcast_last_member_count LAST_MEMBER_COUNT ] [ mcast_last_mem-
ber_interval LAST_MEMBER_INTERVAL ] [ mcast_startup_query_count
STARTUP_QUERY_COUNT ] [ mcast_startup_query_interval
STARTUP_QUERY_INTERVAL ] [ mcast_membership_interval MEMBER-
SHIP_INTERVAL ] [ mcast_querier_interval QUERIER_INTERVAL ] [
mcast_query_interval QUERY_INTERVAL ] [ mcast_query_response_in-
terval QUERY_RESPONSE_INTERVAL ] [ msti MSTI ]
bridge vlan global [ show ] [ dev DEV ] [ vid VID ]
bridge vlan show [ dev DEV ]
bridge vni { add | del } dev DEV vni VNI [ { group | remote } IPADDR ]
bridge vni show [ dev DEV ]
bridge monitor [ all | neigh | link | mdb | vlan ]
OPTIONS
-V, -Version
print the version of the bridge utility and exit.
-s, -stats, -statistics
output more information. If this option is given multiple times,
the amount of information increases. As a rule, the information
is statistics or some time values.
-d, -details
print detailed information about bridge vlan filter entries or
MDB router ports.
-n, -net, -netns <NETNS>
switches bridge to the specified network namespace NETNS. Actu-
ally it just simplifies executing of:
ip netns exec NETNS bridge [ OPTIONS ] OBJECT { COMMAND | help }
to
bridge -n[etns] NETNS [ OPTIONS ] OBJECT { COMMAND | help }
-b, -batch <FILENAME>
Read commands from provided file or standard input and invoke
them. First failure will cause termination of bridge command.
-force Don't terminate bridge command on errors in batch mode. If there
were any errors during execution of the commands, the application
return code will be non zero.
-com, -compressvlans
Show compressed VLAN list. It will show continuous VLANs with the
range instead of separated VLANs. Default is off.
-c[color][={always|auto|never}
Configure color output. If parameter is omitted or always, color
output is enabled regardless of stdout state. If parameter is
auto, stdout is checked to be a terminal before enabling color
output. If parameter is never, color output is disabled. If spec-
ified multiple times, the last one takes precedence. This flag is
ignored if -json is also given.
-j, -json
Output results in JavaScript Object Notation (JSON).
-p, -pretty
When combined with -j generate a pretty JSON output.
-o, -oneline
output each record on a single line, replacing line feeds with
the '\' character. This is convenient when you want to count
records with wc(1) or to grep(1) the output.
BRIDGE - COMMAND SYNTAX
OBJECT
link - Bridge port.
fdb - Forwarding Database entry.
mdb - Multicast group database entry.
vlan - VLAN filter list.
vni - VNI filter list.
COMMAND
Specifies the action to perform on the object. The set of possible ac-
tions depends on the object type. As a rule, it is possible to add,
delete and show (or list ) objects, but some objects do not allow all of
these operations or have some additional commands. The help command is
available for all objects. It prints out a list of available commands
and argument syntax conventions.
If no command is given, some default command is assumed. Usually it is
list or, if the objects of this class cannot be listed, help.
bridge link - bridge port
link objects correspond to the port devices of the bridge.
The corresponding commands set and display port status and bridge spe-
cific attributes.
bridge link set - set bridge specific attributes on a port
dev NAME
interface name of the bridge port
cost COST
the STP path cost of the specified port.
priority PRIO
the STP port priority. The priority value is an unsigned 8-bit
quantity (number between 0 and 255). This metric is used in the
designated port an droot port selection algorithms.
state STATE
the operation state of the port. Except state 0 (disable STP or
BPDU filter feature), this is primarily used by user space
STP/RSTP implementation. One may enter port state name (case in-
sensitive), or one of the numbers below. Negative inputs are ig-
nored, and unrecognized names return an error.
0 - port is in STP DISABLED state. Make this port completely in-
active for STP. This is also called BPDU filter and could be used
to disable STP on an untrusted port, like a leaf virtual devices.
1 - port is in STP LISTENING state. Only valid if STP is enabled
on the bridge. In this state the port listens for STP BPDUs and
drops all other traffic frames.
2 - port is in STP LEARNING state. Only valid if STP is enabled
on the bridge. In this state the port will accept traffic only
for the purpose of updating MAC address tables.
3 - port is in STP FORWARDING state. Port is fully active.
4 - port is in STP BLOCKING state. Only valid if STP is enabled
on the bridge. This state is used during the STP election
process. In this state, port will only process STP BPDUs.
guard on or guard off
Controls whether STP BPDUs will be processed by the bridge port.
By default, the flag is turned off allowed BPDU processing. Turn-
ing this flag on will disables the bridge port if a STP BPDU
packet is received.
If running Spanning Tree on bridge, hostile devices on the net-
work may send BPDU on a port and cause network failure. Setting
guard on will detect and stop this by disabling the port. The
port will be restarted if link is brought down, or removed and
reattached. For example if guard is enable on eth0:
ip link set dev eth0 down; ip link set dev eth0 up
hairpin on or hairpin off
Controls whether traffic may be send back out of the port on
which it was received. This option is also called reflective re-
lay mode, and is used to support basic VEPA (Virtual Ethernet
Port Aggregator) capabilities. By default, this flag is turned
off and the bridge will not forward traffic back out of the re-
ceiving port.
fastleave on or fastleave off
This flag allows the bridge to immediately stop multicast traffic
on a port that receives IGMP Leave message. It is only used with
IGMP snooping is enabled on the bridge. By default the flag is
off.
root_block on or root_block off
Controls whether a given port is allowed to become root port or
not. Only used when STP is enabled on the bridge. By default the
flag is off.
This feature is also called root port guard. If BPDU is received
from a leaf (edge) port, it should not be elected as root port.
This could be used if using STP on a bridge and the downstream
bridges are not fully trusted; this prevents a hostile guest from
rerouting traffic.
learning on or learning off
Controls whether a given port will learn MAC addresses from re-
ceived traffic or not. If learning if off, the bridge will end up
flooding any traffic for which it has no FDB entry. By default
this flag is on.
learning_sync on or learning_sync off
Controls whether a given port will sync MAC addresses learned on
device port to bridge FDB.
flood on or flood off
Controls whether unicast traffic for which there is no FDB entry
will be flooded towards this given port. By default this flag is
on.
hwmode Some network interface cards support HW bridge functionality and
they may be configured in different modes. Currently support
modes are:
vepa - Data sent between HW ports is sent on the wire to the ex-
ternal switch.
veb - bridging happens in hardware.
bcast_flood on or bcast_flood off
Controls flooding of broadcast traffic on the given port. By de-
fault this flag is on.
mcast_flood on or mcast_flood off
Controls whether multicast traffic for which there is no MDB en-
try will be flooded towards this given port. By default this flag
is on.
mcast_max_groups MAX_GROUPS
Sets the maximum number of MDB entries that can be registered for
a given port. Attempts to register more MDB entries at the port
than this limit allows will be rejected, whether they are done
through netlink (e.g. the bridge tool), or IGMP or MLD membership
reports. Setting a limit to 0 has the effect of disabling the
limit. The default value is 0. See also the ip link option
mcast_hash_max.
mcast_router MULTICAST_ROUTER
This flag is almost the same as the per-VLAN flag, see below, ex-
cept its value can only be set in the range 0-2. The default is
1 where the bridge figures out automatically where an IGMP/MLD
querier, MRDISC capable device, or PIM router, is located. Set-
ting this flag to 2 is useful in cases where the multicast router
does not indicate its presence in any meaningful way (e.g. older
versions of SMCRoute, or mrouted), or when there is a need for
forwarding both known and unknown IP multicast to a sec-
ondary/backup router.
mcast_to_unicast on or mcast_to_unicast off
Controls whether a given port will replicate packets using uni-
cast instead of multicast. By default this flag is off.
This is done by copying the packet per host and changing the mul-
ticast destination MAC to a unicast one accordingly.
mcast_to_unicast works on top of the multicast snooping feature
of the bridge. Which means unicast copies are only delivered to
hosts which are interested in it and signalized this via IGMP/MLD
reports previously.
This feature is intended for interface types which have a more
reliable and/or efficient way to deliver unicast packets than
broadcast ones (e.g. WiFi).
However, it should only be enabled on interfaces where no
IGMPv2/MLDv1 report suppression takes place. IGMP/MLD report sup-
pression issue is usually overcome by the network daemon (suppli-
cant) enabling AP isolation and by that separating all STAs.
Delivery of STA-to-STA IP multicast is made possible again by en-
abling and utilizing the bridge hairpin mode, which considers the
incoming port as a potential outgoing port, too (see hairpin op-
tion). Hairpin mode is performed after multicast snooping,
therefore leading to only deliver reports to STAs running a mul-
ticast router.
neigh_suppress on or neigh_suppress off
Controls whether neigh discovery (arp and nd) proxy and suppres-
sion is enabled on the port. By default this flag is off.
neigh_vlan_suppress on or neigh_vlan_suppress off
Controls whether per-VLAN neigh discovery (arp and nd) proxy and
suppression is enabled on the port. When on, the bridge link op-
tion neigh_suppress has no effect and the per-VLAN state is set
using the bridge vlan option neigh_suppress. By default this flag
is off.
vlan_tunnel on or vlan_tunnel off
Controls whether vlan to tunnel mapping is enabled on the port.
By default this flag is off.
isolated on or isolated off
Controls whether a given port will be isolated, which means it
will be able to communicate with non-isolated ports only. By de-
fault this flag is off.
locked on or locked off
Controls whether a port is locked or not. When locked, non-link-
local frames received through the port are dropped unless an FDB
entry with the MAC source address points to the port. The common
use case is IEEE 802.1X where hosts can authenticate themselves
by exchanging EAPOL frames with an authenticator. After authenti-
cation is complete, the user space control plane can install a
matching FDB entry to allow traffic from the host to be forwarded
by the bridge. When learning is enabled on a locked port, the
no_linklocal_learn bridge option needs to be on to prevent the
bridge from learning from received EAPOL frames. By default this
flag is off.
mab on or mab off
Controls whether MAC Authentication Bypass (MAB) is enabled on
the port or not. MAB can only be enabled on a locked port that
has learning enabled. When enabled, FDB entries are learned from
received traffic and have the "locked" FDB flag set. The flag can
only be set by the kernel and it indicates that the FDB entry
cannot be used to authenticate the corresponding host. User space
can decide to authenticate the host by replacing the FDB entry
and clearing the "locked" FDB flag. Locked FDB entries can roam
to unlocked (authorized) ports in which case the "locked" flag is
cleared. FDB entries cannot roam to locked ports regardless of
MAB being enabled or not. Therefore, locked FDB entries are only
created if an FDB entry with the given {MAC, VID} does not al-
ready exist. This behavior prevents unauthenticated hosts from
disrupting traffic destined to already authenticated hosts.
Locked FDB entries act like regular dynamic entries with respect
to forwarding and aging. By default this flag is off.
backup_port DEVICE
If the port loses carrier all traffic will be redirected to the
configured backup port
nobackup_port
Removes the currently configured backup port
backup_nhid NHID
The FDB nexthop object ID (see ip-nexthop(8)) to attach to pack-
ets being redirected to a backup port that has VLAN tunnel map-
ping enabled (via the vlan_tunnel option). Setting a value of 0
(default) has the effect of not attaching any ID.
self link setting is configured on specified physical device
master link setting is configured on the software bridge (default)
-t, -timestamp
display current time when using monitor option.
bridge link show - list ports configuration for all bridges.
This command displays ports configuration and flags for all bridges by
default.
dev DEV
only display the specific bridge port named DEV.
master DEVICE
only display ports of the bridge named DEVICE. This is similar to
"ip link show master <bridge_device>" command.
bridge fdb - forwarding database management
fdb objects contain known Ethernet addresses on a link.
The corresponding commands display fdb entries, add new entries, append
entries, and delete old ones.
bridge fdb add - add a new fdb entry
This command creates a new fdb entry.
LLADDR the Ethernet MAC address.
dev DEV
the interface to which this address is associated.
local - is a local permanent fdb entry, which means that the
bridge will not forward frames with this destination MAC address
and VLAN ID, but terminate them locally. This flag is default un-
less "static" or "dynamic" are explicitly specified.
permanent - this is a synonym for "local"
static - is a static (no arp) fdb entry
dynamic - is a dynamic reachable age-able fdb entry
self - the operation is fulfilled directly by the driver for the
specified network device. If the network device belongs to a mas-
ter like a bridge, then the bridge is bypassed and not notified
of this operation (and if the device does notify the bridge, it
is driver-specific behavior and not mandated by this flag, check
the driver for more details). The "bridge fdb add" command can
also be used on the bridge device itself, and in this case, the
added fdb entries will be locally terminated (not forwarded). In
the latter case, the "self" flag is mandatory. The flag is set by
default if "master" is not specified.
master - if the specified network device is a port that belongs
to a master device such as a bridge, the operation is fulfilled
by the master device's driver, which may in turn notify the port
driver too of the address. If the specified device is a master
itself, such as a bridge, this flag is invalid.
router - the destination address is associated with a router.
Valid if the referenced device is a VXLAN type device and has
route short circuit enabled.
use - the address is in use. User space can use this option to
indicate to the kernel that the fdb entry is in use.
extern_learn - this entry was learned externally. This option can
be used to indicate to the kernel that an entry was hardware or
user-space controller learnt dynamic entry. Kernel will not age
such an entry.
sticky - this entry will not change its port due to learning.
The next command line parameters apply only when the specified device DEV
is of type VXLAN.
dst IPADDR
the IP address of the destination VXLAN tunnel endpoint where the
Ethernet MAC ADDRESS resides.
src_vni VNI
the src VNI Network Identifier (or VXLAN Segment ID) this entry
belongs to. Used only when the vxlan device is in external or
collect metadata mode. If omitted the value specified at vxlan
device creation will be used.
vni VNI
the VXLAN VNI Network Identifier (or VXLAN Segment ID) to use to
connect to the remote VXLAN tunnel endpoint. If omitted the
value specified at vxlan device creation will be used.
port PORT
the UDP destination PORT number to use to connect to the remote
VXLAN tunnel endpoint. If omitted the default value is used.
via DEVICE
device name of the outgoing interface for the VXLAN device driver
to reach the remote VXLAN tunnel endpoint.
nhid NHID
ecmp nexthop group for the VXLAN device driver to reach remote
VXLAN tunnel endpoints.
bridge fdb append - append a forwarding database entry
This command adds a new fdb entry with an already known LLADDR. Valid
only for multicast link layer addresses. The command adds support for
broadcast and multicast Ethernet MAC addresses. The Ethernet MAC ad-
dress is added multiple times into the forwarding database and the vxlan
device driver sends a copy of the data packet to each entry found.
The arguments are the same as with bridge fdb add.
bridge fdb delete - delete a forwarding database entry
This command removes an existing fdb entry.
The arguments are the same as with bridge fdb add.
bridge fdb replace - replace a forwarding database entry
If no matching entry is found, a new one will be created instead.
The arguments are the same as with bridge fdb add.
bridge fdb show - list forwarding entries.
This command displays the current forwarding table.
With the -statistics option, the command becomes verbose. It prints out
the last updated and last used time for each entry.
bridge fdb get - get bridge forwarding entry.
lookup a bridge forwarding table entry.
LLADDR the Ethernet MAC address.
dev DEV
the interface to which this address is associated.
brport DEV
the bridge port to which this address is associated. same as dev
above.
br DEV the bridge to which this address is associated.
self - the address is associated with the port drivers fdb. Usually
hardware.
master - the address is associated with master devices fdb. Usually
software (default).
bridge fdb flush - flush bridge forwarding table entries.
flush the matching bridge forwarding table entries. Some options below
have a negated form when "no" is prepended to them (e.g. permanent and
nopermanent).
dev DEV
the target device for the operation. If the device is a bridge
port and "master" is set then the operation will be fulfilled by
its master device's driver and all entries pointing to that port
will be deleted.
brport DEV
the target bridge port for the operation. If the bridge device is
specified then only entries pointing to the bridge itself will be
deleted. Note that the target device specified by this option
will override the one specified by dev above.
vlan VID
the target VLAN ID for the operation. Match forwarding table en-
tries only with the specified VLAN ID.
src_vni VNI
the src VNI Network Identifier (or VXLAN Segment ID) for the op-
eration. Match forwarding table entries only with the specified
VNI. Valid if the referenced device is a VXLAN type device.
nhid NHID
the ECMP nexthop group for the operation. Match forwarding table
entries only with the specified NHID. Valid if the referenced de-
vice is a VXLAN type device.
vni VNI
the VXLAN VNI Network Identifier (or VXLAN Segment ID) for the
operation. Match forwarding table entries only with the specified
VNI. Valid if the referenced device is a VXLAN type device.
port PORT
the UDP destination PORT number for the operation. Match forward-
ing table entries only with the specified PORT. Valid if the ref-
erenced device is a VXLAN type device.
dst IPADDR
the IP address of the destination VXLAN tunnel endpoint for the
operation. Match forwarding table entries only with the specified
IPADDR. Valid if the referenced device is a VXLAN type device.
self the operation is fulfilled directly by the driver for the speci-
fied network device. If the network device belongs to a master
like a bridge, then the bridge is bypassed and not notified of
this operation. The "bridge fdb flush" command can also be used
on the bridge device itself. The flag is set by default if "mas-
ter" is not specified.
master if the specified network device is a port that belongs to a mas-
ter device such as a bridge, the operation is fulfilled by the
master device's driver. Flush with both 'master' and 'self' is
not recommended with attributes that are not supported by all de-
vices (e.g., vlan, vni). Such command will be handled by bridge
or VXLAN driver, but will return an error from the driver that
does not support the attribute. Instead, run flush twice - once
with 'self' and once with 'master', and each one with the sup-
ported attributes.
[no]permanent
if specified then only permanent entries will be deleted or re-
spectively if "no" is prepended then only non-permanent entries
will be deleted.
[no]static
if specified then only static entries will be deleted or respec-
tively if "no" is prepended then only non-static entries will be
deleted.
[no]dynamic
if specified then only dynamic entries will be deleted or respec-
tively if "no" is prepended then only non-dynamic (static or per-
manent) entries will be deleted.
[no]added_by_user
if specified then only entries with added_by_user flag will be
deleted or respectively if "no" is prepended then only entries
without added_by_user flag will be deleted.
[no]extern_learn
if specified then only entries with extern_learn flag will be
deleted or respectively if "no" is prepended then only entries
without extern_learn flag will be deleted.
[no]sticky
if specified then only entries with sticky flag will be deleted
or respectively if "no" is prepended then only entries without
sticky flag will be deleted.
[no]offloaded
if specified then only entries with offloaded flag will be
deleted or respectively if "no" is prepended then only entries
without offloaded flag will be deleted.
[no]router
if specified then only entries with router flag will be deleted
or respectively if "no" is prepended then only entries without
router flag will be deleted. Valid if the referenced device is a
VXLAN type device.
bridge mdb - multicast group database management
mdb objects contain known IP or L2 multicast group addresses on a link.
The corresponding commands display mdb entries, add new entries, replace
entries and delete old ones.
bridge mdb add - add a new multicast group database entry
This command creates a new mdb entry.
dev DEV
the interface where this group address is associated.
port PORT
the port whose link is known to have members of this multicast
group.
grp GROUP
the multicast group address (IPv4, IPv6 or L2 multicast) whose
members reside on the link connected to the port.
permanent - the mdb entry is permanent. Optional for IPv4 and
IPv6, mandatory for L2.
temp - the mdb entry is temporary (default)
src SOURCE
optional source IP address of a sender for this multicast group.
If IGMPv3 for IPv4, or MLDv2 for IPv6 respectively, are enabled
it will be included in the lookup when forwarding multicast traf-
fic.
vid VID
the VLAN ID which is known to have members of this multicast
group.
filter_mode include or filter_mode exclude
controls whether the sources in the entry's source list are in
INCLUDE or EXCLUDE mode. Can only be set for (*, G) entries.
source_list SOURCE_LIST
optional list of source IP addresses of senders for this multi-
cast group, separated by a ','. Whether the entry forwards pack-
ets from these senders or not is determined by the entry's filter
mode, which becomes a mandatory argument. Can only be set for (*,
G) entries.
proto PROTO
the routing protocol identifier of this mdb entry. Can be a num-
ber or a string from the file /etc/iproute2/rt_protos. If the
routing protocol is not given, then static is assumed.
The next command line parameters apply only when the specified device DEV
is of type VXLAN.
dst IPADDR
the IP address of the destination VXLAN tunnel endpoint where the
multicast receivers reside.
dst_port DST_PORT
the UDP destination port number to use to connect to the remote
VXLAN tunnel endpoint. If omitted, the value specified at VXLAN
device creation will be used.
vni VNI
the VXLAN VNI Network Identifier to use to connect to the remote
VXLAN tunnel endpoint. If omitted, the value specified at VXLAN
device creation will be used or the source VNI when the VXLAN de-
vice is in external mode.
src_vni SRC_VNI
the source VNI Network Identifier this entry belongs to. Used
only when the VXLAN device is in external mode. If omitted, the
value specified at VXLAN device creation will be used.
via DEV
device name of the outgoing interface for the VXLAN device to
reach the remote VXLAN tunnel endpoint.
The 0.0.0.0 and :: MDB entries are special catchall entries used to flood
IPv4 and IPv6 unregistered multicast packets, respectively. Therefore,
when these entries are programmed, the catchall 00:00:00:00:00:00 FDB en-
try will only flood broadcast, unknown unicast and link-local multicast.
bridge mdb delete - delete a multicast group database entry
This command removes an existing mdb entry.
The arguments are the same as with bridge mdb add.
bridge mdb replace - replace a multicast group database entry
If no matching entry is found, a new one will be created instead.
The arguments are the same as with bridge mdb add.
bridge mdb show - list multicast group database entries
This command displays the current multicast group membership table. The
table is populated by IGMP and MLD snooping in the bridge driver auto-
matically. It can be altered by bridge mdb add and bridge mdb del com-
mands manually too.
dev DEV
the interface only whose entries should be listed. Default is to
list all bridge interfaces.
With the -details option, the command becomes verbose. It prints out the
ports known to have a connected router.
With the -statistics option, the command displays timer values for mdb
and router port entries.
bridge mdb get - get multicast group database entry.
This command retrieves a multicast group database entry based on its
key.
dev DEV
the interface where this group address is associated.
grp GROUP
the multicast group address (IPv4, IPv6 or L2 multicast).
src SOURCE
the source IP address. Only relevant when retrieving an (S, G)
entry.
vid VID
the VLAN ID. Only relevant when the bridge is VLAN-aware.
src_vni SRC_VNI
the source VNI Network Identifier. Only relevant when the VXLAN
device is in external mode.
bridge mdb flush - flush multicast group database entries.
This command flushes the matching multicast group database entries.
dev DEV
the interface where this group address is associated.
port PORT
the target port for the operation. If the bridge device is speci-
fied then only entries pointing to the bridge itself will be
deleted.
vid VID
the VLAN ID for the operation. Match entries only with the speci-
fied VLAN ID.
src_vni SRC_VNI
the source VNI Network Identifier for the operation. Match en-
tries only with the specified source VNI.
proto PROTO
the routing protocol identifier for the operation. Match entries
only with the specified routing protocol. Can be a number or a
string from the file /etc/iproute2/rt_protos.
[no]permanent
if specified then only permanent entries will be deleted or re-
spectively if "no" is prepended then only non-permanent (temp)
entries will be deleted.
dst IPADDR
the IP address of the destination VXLAN tunnel endpoint where the
multicast receivers reside. Match entries only with the specified
destination IP.
dst_port DST_PORT
the UDP destination port number to use to connect to the remote
VXLAN tunnel endpoint. Match entries only with the specified des-
tination port number.
vni VNI
the VXLAN VNI Network Identifier to use to connect to the remote
VXLAN tunnel endpoint. Match entries only with the specified des-
tination VNI.
bridge mst - multiple spanning tree port states
In the multiple spanning tree (MST) model, the active paths through a
network can be different for different VLANs. In other words, a bridge
port can simultaneously forward one subset of VLANs, while blocking an-
other.
Provided that the mst_enable bridge option is enabled, a group of VLANs
can be forwarded along the same spanning tree by associating them with
the same instance (MSTI) using bridge vlan global set.
bridge mst set - set multiple spanning tree state
Set the spanning tree state for DEV, in the multiple spanning tree in-
stance MSTI, to STP_STATE.
dev DEV
Interface name of the bridge port.
msti MSTI
The multiple spanning tree instance.
state STP_STATE
The spanning tree state, see the state option of bridge link set
for supported states.
bridge mst show - list MST states
List current MST port states in every MSTI.
dev DEV
If specified, only display states of the bridge port with this
interface name.
bridge vlan - VLAN filter list
vlan objects contain known VLAN IDs for a link.
The corresponding commands display vlan filter entries, add new entries,
and delete old ones.
bridge vlan add - add a new vlan filter entry
This command creates a new vlan filter entry.
dev NAME
the interface with which this vlan is associated.
vid VID
the VLAN ID that identifies the vlan.
tunnel_info TUNNEL_ID
the TUNNEL ID that maps to this vlan. The tunnel id is set in
dst_metadata for every packet that belongs to this vlan (applica-
ble to bridge ports with vlan_tunnel flag set).
pvid the vlan specified is to be considered a PVID at ingress. Any
untagged frames will be assigned to this VLAN.
untagged
the vlan specified is to be treated as untagged on egress.
self the vlan is configured on the specified physical device. Required
if the device is the bridge device.
master the vlan is configured on the software bridge (default).
bridge vlan delete - delete a vlan filter entry
This command removes an existing vlan filter entry.
The arguments are the same as with bridge vlan add. The pvid and un-
tagged flags are ignored.
bridge vlan set - change vlan filter entry's options
This command changes vlan filter entry's options.
dev NAME
the interface with which this vlan is associated.
vid VID
the VLAN ID that identifies the vlan.
state STP_STATE
the operation state of the vlan. One may enter STP state name
(case insensitive), or one of the numbers below. Negative inputs
are ignored, and unrecognized names return an error. Note that
the state is set only for the vlan of the specified device, e.g.
if it is a bridge port then the state will be set only for the
vlan of the port.
0 - vlan is in STP DISABLED state. Make this vlan completely in-
active for STP. This is also called BPDU filter and could be used
to disable STP on an untrusted vlan.
1 - vlan is in STP LISTENING state. Only valid if STP is enabled
on the bridge. In this state the vlan listens for STP BPDUs and
drops all other traffic frames.
2 - vlan is in STP LEARNING state. Only valid if STP is enabled
on the bridge. In this state the vlan will accept traffic only
for the purpose of updating MAC address tables.
3 - vlan is in STP FORWARDING state. This is the default vlan
state.
4 - vlan is in STP BLOCKING state. Only valid if STP is enabled
on the bridge. This state is used during the STP election
process. In this state, the vlan will only process STP BPDUs.
mcast_max_groups MAX_GROUPS
Sets the maximum number of MDB entries that can be registered for
a given VLAN on a given port. A VLAN-specific equivalent of the
per-port option of the same name, see above for details.
Note that this option is only available when ip link option
mcast_vlan_snooping is enabled.
mcast_router MULTICAST_ROUTER
configure this vlan and interface's multicast router mode, note
that only modes 0 - 2 are available for bridge devices. A vlan
and interface with a multicast router will receive all multicast
traffic. MULTICAST_ROUTER may be either
0 - to disable multicast router.
1 - to let the system detect the presence of routers (default).
2 - to permanently enable multicast traffic forwarding on this
vlan and interface.
3 - to temporarily mark this vlan and port as having a multicast
router, i.e. enable multicast traffic forwarding. This mode is
available only for ports.
neigh_suppress on or neigh_suppress off
Controls whether neigh discovery (arp and nd) proxy and suppres-
sion is enabled for a given VLAN on a given port. By default this
flag is off.
Note that this option only takes effect when bridge link option
neigh_vlan_suppress is enabled for a given port.
bridge vlan show - list vlan configuration.
This command displays the current VLAN filter table.
With the -details option, the command becomes verbose. It displays the
per-vlan options.
With the -statistics option, the command displays per-vlan traffic sta-
tistics.
bridge vlan tunnelshow - list vlan tunnel mapping.
This command displays the current vlan tunnel info mapping.
bridge vlan global set - change vlan filter entry's global options
This command changes vlan filter entry's global options.
dev NAME
the interface with which this vlan is associated. Only bridge de-
vices are supported for global options.
vid VID
the VLAN ID that identifies the vlan.
mcast_snooping MULTICAST_SNOOPING
turn multicast snooping for VLAN entry with VLAN ID on (MULTI-
CAST_SNOOPING > 0) or off (MULTICAST_SNOOPING == 0). Default is
on.
mcast_querier MULTICAST_QUERIER
enable (MULTICAST_QUERIER > 0) or disable (MULTICAST_QUERIER ==
0) IGMP/MLD querier, ie sending of multicast queries by the
bridge. Default is disabled.
mcast_igmp_version IGMP_VERSION
set the IGMP version. Default is 2.
mcast_mld_version MLD_VERSION
set the MLD version. Default is 1.
mcast_last_member_count LAST_MEMBER_COUNT
set multicast last member count, ie the number of queries the
bridge will send before stopping forwarding a multicast group af-
ter a "leave" message has been received. Default is 2.
mcast_last_member_interval LAST_MEMBER_INTERVAL
interval between queries to find remaining members of a group,
after a "leave" message is received.
mcast_startup_query_count STARTUP_QUERY_COUNT
set the number of queries to send during startup phase. Default
is 2.
mcast_startup_query_interval STARTUP_QUERY_INTERVAL
interval between queries in the startup phase.
mcast_membership_interval MEMBERSHIP_INTERVAL
delay after which the bridge will leave a group, if no membership
reports for this group are received.
mcast_querier_interval QUERIER_INTERVAL
interval between queries sent by other routers. If no queries are
seen after this delay has passed, the bridge will start to send
its own queries (as if mcast_querier was enabled).
mcast_query_interval QUERY_INTERVAL
interval between queries sent by the bridge after the end of the
startup phase.
mcast_query_response_interval QUERY_RESPONSE_INTERVAL
set the Max Response Time/Maximum Response Delay for IGMP/MLD
queries sent by the bridge.
msti MSTI
associate the VLAN with the specified multiple spanning tree in-
stance (MSTI).
bridge vlan global show - list global vlan options.
This command displays the global VLAN options for each VLAN entry.
dev DEV
the interface only whose VLAN global options should be listed.
Default is to list all bridge interfaces.
vid VID
the VLAN ID only whose global options should be listed. Default
is to list all vlans.
bridge vni - VNI filter list
vni objects contain known VNI IDs for a dst metadata vxlan link.
The corresponding commands display vni filter entries, add new entries,
and delete old ones.
bridge vni add - add a new vni filter entry
This command creates a new vni filter entry.
dev NAME
the interface with which this vni is associated.
vni VNI
the VNI ID that identifies the vni.
remote IPADDR
specifies the unicast destination IP address to use in outgoing
packets when the destination link layer address is not known in
the VXLAN device forwarding database. This parameter cannot be
specified with the group.
group IPADDR
specifies the multicast IP address to join for this VNI
bridge vni del - delete a new vni filter entry
This command removes an existing vni filter entry.
The arguments are the same as with bridge vni add.
bridge vni show - list vni filtering configuration.
This command displays the current vni filter table.
With the -statistics option, the command displays per-vni traffic sta-
tistics.
dev NAME
shows vni filtering table associated with the vxlan device
bridge monitor - state monitoring
The bridge utility can monitor the state of devices and addresses con-
tinuously. This option has a slightly different format. Namely, the
monitor command is the first in the command line and then the object
list follows:
bridge monitor [ all | OBJECT-LIST ]
OBJECT-LIST is the list of object types that we want to monitor. It may
contain link, fdb, vlan and mdb. If no file argument is given, bridge
opens RTNETLINK, listens on it and dumps state changes in the format de-
scribed in previous sections.
If a file name is given, it does not listen on RTNETLINK, but opens the
file containing RTNETLINK messages saved in binary format and dumps
them.
NOTES
This command uses facilities added in Linux 3.0.
Although the forwarding table is maintained on a per-bridge device basis
the bridge device is not part of the syntax. This is a limitation of the
underlying netlink neighbour message protocol. When displaying the for-
warding table, entries for all bridges are displayed. Add/delete/modify
commands determine the underlying bridge device based on the bridge to
which the corresponding ethernet device is attached.
SEE ALSO
ip(8)
BUGS
Please direct bugreports and patches to: <netdev@vger.kernel.org>
AUTHOR
Original Manpage by Stephen Hemminger
iproute2 1 August 2012 BRIDGE(8)
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